Orthogonal mutations for heterodimerization

Abstract

Heterodimerizing domains with orthogonal mutations that drive heterodimerization, in particular heterodimerizing antibody CH3 domains, heterodimeric polypeptides comprising such heterodimerizing domains, and antibody constructs comprising such heterodimeric polypeptides, are provided.

What is claimed is: 
     
       1. An antibody construct, comprising:
 a first polypeptide chain, a second polypeptide chain, a third polypeptide chain, and a fourth polypeptide chain, wherein: 
 a) the first polypeptide chain comprises a V L  domain, a CH3 domain having the amino acid sequence of SEQ ID NO: 5, a CH2 domain having the amino acid sequence of SEQ ID NO: 6, and a CH3 domain having the amino acid sequence of SEQ ID NO: 7,
 wherein the domains are ordered, from N terminus to C terminus: V L -CH3-CH2-CH3; 
 
 b) the second polypeptide chain comprises a V H  domain and a CH3 domain having the amino acid sequence of SEQ ID NO: 8, wherein the domains are ordered, from N terminus to C terminus: V H -CH3, wherein the V L  domain of the first polypeptide chain and the V H  domain of the second polypeptide chain associate to form a first antigen binding site; 
 c) the third polypeptide chain comprises a V L  domain, a C L  domain having the amino acid sequence of SEQ ID NO: 9, a CH2 domain having the amino acid sequence of SEQ ID NO: 10, and a CH3 domain having the amino acid sequence of SEQ ID NO: 11,
 wherein the domains are ordered, from N terminus to C terminus: V L -C L -CH2-CH3; and 
 
 d) a fourth polypeptide chain comprising a V H  domain and a CH1 domain having the amino acid sequence of SEQ ID NO: 12, wherein the domains are ordered, from N terminus to C terminus: V H -CH1, wherein the V L  domain of the third polypeptide chain and the V H  domain of the fourth polypeptide chain associate to form a second antigen binding site.